Azo dyestuffs



Patented Nov. 19, 1957 1 2 2,813,856 wherein each of R6, R7 and Rsstands for a radical of AZ YES FS the benzene or naphthalene series, R9stands for a radical Willy Steinemann and Walter Wehrli, Basel,Switzerland, f the benzene, naphthalene or BY WhllP R assignors, bymesne assignments, to Saul & Co., New- R2, 3 W, v and n have thepfevlollsly-descrlbed Slgmfiark, N. J., as nominee of Fidelity UnionTrust Com- 5 Games. pany, executive trustee under Sandoz Trust A furtherobject of the invention is the embodiment of N0 Drawing. ApplicationApril 24), 1953, an eflicient method for the preparation of the afore-Serial No. 349,966 described azo dyestuffs. This object is realizedaccording Claims priority, application Switzerland April 25, 1952 to thepresent invention by reacting one mole of a di- 18 Claims (CL 2 0 174 10carboxylic acid which corresponds to the formula This application is acontinuation-in-part of application F0 043433430: Serial No. 236,266,filed July 11, 1951 (and abandoned (I) Since the filing of the presentapplication). wherein A stands for hydrogen, chlorine, bromine or Thepresent invention relates to azo dyestufis and to y and z stands forchlorine or bromine with: the preparation thereof, (a) Two moles of anamlnoazo compound wh1ch cor- It is a primary object of this invention toembody a responds to the formula valuable group of disazo and polyazodyestuffs which dye 10 cotton and fibers of regenerated cellulose inyellow to orange-brown shades, which dyeings, as such or in theaftercoppered state, are characterized by enhanced prop- H00 erties,such as purity of shade and superior fastness to or with; light.

(b) Two moles of a mixture of two difierent aminoazo T 1118 ob ect isrealized according to the present invention Compounds which correspondto the formula by the group of azo dyestnlfs corresponding to theformula w a tlQ-X-Rr-NH: w

y XR1-NHCOC=COOb H00 1 I or with: E0 0 c y (0) Two moles of a mixture ofan aminoazo compound wherein X stands for which corresponds to theformula 10 'll O T E I O XRiNHa 0 H H -N=N or (N=N-Rz-)n-1N=N-; each ofR1 ml 1,

and R2 stands for a radical of the benzene, diphenyl, and an aminoazocompound which corresponds to the stilbene, naphthalene, pyrazolone oracetoacetylarninoaryl formula series; one y stands for OH and the othery stands for HlNRe[-N=NR1(N=N-R8),.-1]-l-N=N-Rv hydrogen; w representshydrogen, halogen, lower alkyl, 40 in which formulae R1, R6, R7, Rs, R9,X, w, y and n have nitro, acylamino or 4O3H; one v stands for hydrogenthe previously-recited significances.

and the other v for hydrogen, chlorine, bromine or methyl; Aparticularly interesting sub-group of dyestufls within n is one of theintegers 1 and 2; and b is either identical the scope of the presentinvention correspond to the with the moiety a or mutually different fromsuch moiety formula H033 R, RI SIOaH y XGNHCC=CHCHN X' 1/ R1 8 i, l R, H0 0 C y u 0 OR a or is a radical of a non-metallizable mono-, disortrisazo wherein X stands for compound of the benzene, naphthalene orpyrene series.

The aforesaid group of azo dyestulfs comprises dye- I fi O stutfs whichcorrespond to the formula 0 H 0 ll wherein each of R1, R11, R2 and R22stands for a radical or -N=N, one y and one y each stands for H, and theof the benzene, diphenyl, stilbene, naphthalene, pyrazoother y and theother y each stands for OH, R1 stands for lone or acetoacetylaminoarylseries, one y and one y each H, lower alkyl or lower alkoxy, R2 standsfor H, lower stands for OH and the other y and y each stands for alkyl,lower alkoxy hydrogen, while v, w and n have the afore-indicatedsignificances.

Another group of azo dyestufis comprised within the dyestuifs of thepresent invention correspond to the formula NH-C-lower alkyl II orNH.COO-lower alkyl and R's stands for H or methyl. Lower alkyl is forinstance methyl, ethyl, propyl,

o u butyl, etc., and lower alkoxy is for instance methoxy, ethoxy,propoxy, butoxy, etc.

The dyestufis of this sub-group can be prepared by starting from anappropriate aminoazo dyestufi which corresponds to the formula R1 H ywherein X, y, R and R2 have the precedingly-indicated significances, andreacting the same with a dihalide of the formula wherein R3 has theprecedingly-indicated significance, and hat stands for C1 or Br, usingtwo moles of aminoazo dyestufi per mole of dihalide.

A sub-group of the aforedescribed disazo and polyazo dyestuffs can alsobe prepared by diazotizing or tetrazotizing the corresponding monoordi-amines of the formula wherein A has the previously-indicatedsignificance, one t stands for the amino groupand the other t stands foramino, nitro or a readily saponifiable acylamino group, and each of R1and R2 stands for an aryl radical, and then coupling the products withazo components which may contain substituents, including arylazo groupsor .diazotizable amino groups, and then if desired carrying out furthercoupling reactions with the so-obtained azo compounds, twhen it standsfor nitro or a readily saponifiable acylamino groupbeing converted intothe diazo at any stage of the preparation of the dyestuff by reductionor saponification and diazotization. The reactants are here so selectedthat the resultant disazo or polyazo dyestuifs containin the moleculethereof, (a) at least one end-positioned metallizableortho-hydroxycarboxy grouping but no other metallizable grouping, (b)the requisite number of solubilizing groups to impart water-solubilitythereto, and (c) at most five azo bridges. Another embodiment of processfor preparing disazo and polyazo dyestuffs encompassed by this inventioninvolves coupling one mole of a compound of the formula wherein A hasthe previously-indicated significance and each of Ra and R4 is theradical of an 2120 component, with two moles of a diazo compound or of adiazornonoazo compound which contains no other metallizable groupingthan an end-positioned ortho-hydroxycarboxy grouping, or simultaneouslyor in any desired sequence with two moles of a mixture of two mutuallydifierent such compounds or of one such compound and one nonmetallizablediazo or diazomonoazo ordiazodisazo compound, with the proviso that theresultant disazo or polyazo dyest-ufis contain in the molecule thereof(a) at least one end-positioned metallizable ortho-hydroxycarboxygrouping but no other metallizable grouping, (b) the requisite number ofsolubilizing groups to impart watersolubility thereto, and (c) at mostfive azo bridges.

It is also possible to combine the two last-mentioned procedures bycoupling one mole of a monohydroxy compound of the formula wherein A hasthe previously-recited significance, one R5 is the radical of an azocomponent and the other R5 is an aryl radical which contains adiazotizable amino group or a nitro group which is convertible into adiazotizable amino group or a readily saponifiable acylamino group, onthe one hand with (a) one mole of a suitable diazo compound or diazoazocompound and, on the other hand-if necessary, after conversion of thenitro group or the readily saponifiable acylamino group into the diazogroupdiazotizing and coupling with one mol of an appropriate azocomponent, which may contain any desired substituents including arylazogroups or diazotizable amino groups, it being possible to carry outadditional coupling reactions before or after the aforesaiddiazotization and coupling.

The joining together of the two moles of aminoazo compounds inaccordance with the first hereinbeforedescribed process is carried outwith the aid of an unsaturated dicarboxylic acid halide of Formula I,supra. Illustrative of such halides are the dichlorides and dibromidesof fumaric and maleic acid, methyl-fumaric acid, methyl-maleic acid andchlorofumaric or bromofumaric acid. In order to compensate for lossesdue to hydrolysis, the dicarboxylic acid halides may be used in slightexcess. In carrying out the process, the aminoazo compounds aredissolved in water, and the dicarboxylic acid halide (I) then added,preferably at a low temperature (about 0 to 30 C.). The reaction mixtureis stirred vigorously, and liberated hydrogen halide is continuouslyneutralized by the addition of acid-binding agents such e. g. as sodiumbicarbonate, sodium carbonate, sodium hydroxide, the correspondinglithium or potassium compounds, alkali metal acetates, alkaline earthmetal oxides or carbonates, magnesium oxide, or suitable tertiaryorganic amines such as N,N-dimethylaminobenzene and the like. Thedicarboxylic acid may, if desired, be diluted with an inert solvent,such for example as benzene,

methylbenzene, chlorobenzene, carbon tetrachloride or chloroform. Thecondensation is ended when free NHz is no longer detectable. Thereaction product is partly present in precipitated form, the remainderbeing precipitated from the reaction solution by salting out or, in somecases, by acidification, after which the reaction product is filteredoff, washed if necessary, and dried.

A unitary dyestufi is obtained by joining together two moles of the sameaminoazo compound with one mole of a dicarboxylic acid halide (I). Onthe other hand, when two moles of a mixture of two different aminoazocompounds are condensed with a dicarboxylic acid halide (I), a mixtureof symmetrical and asymmetrical dicarboxylic acid derivativesisobtained. The mixture contains, as predominating ingredient, acomponent of the formula wherein R stands for the radical of oneaminoazo compound which is acylated in the amino group and T stands forthe radical of the other such aminoazo compound, and Q stands for theradical of the dicarboxylic acid from the formulae R-QR and T--Q-T Thetwo difierent aminoazo compounds can be condensed together in the molarproportion 1:1 with the dicarboX- ylic acid halide (I). Valuabledyestuffs can also be obtained with other mixture proportions, such forexample as those involved in condensation products from 1 part ofdicarboxylic acid halide (I) and two aminoazo compounds in theproportion of 4:1, 3:1, 2:1, 1:2, 1:3, or 1:4; in fact, some of thesepossess properties which are superior to those of the dyestufis whereinone proportion of dicarboxylic acid (I) is condensed with twoproportions of two aminoazo compounds in the 1:1 proportion. Suchmixtures and the preparation thereof constitute a further object of theinvention.

The disazo and polyazo dyestuifs of the present invention areparticularly suitable for dyeing and printing cotton and fibers ofregenerated cellulose. The dyeings and prints are characterized bypurity of color, good fastness to light and good fastness to wettreatments. They may be treated with metal-yielding agents, and suchtreatment may be carried out by a single bath process or by anafter-metallization process. The treatment with metalyielding agents inmany cases imparts to the dyeings enhanced fastness to light and to wettreatments.

The dyestufi mixtures within the purview of the present invention canalso be prepared by admixing the corresponding unitary dyestufis, and inmany cases the resultant mixtures are the full equivalents of thoseobtained during the manufacture of the dyestuffs by the aforedescribedprocesses.

The following examples set forth representative exemplary embodiments ofthe invention, and these examples are intended to be solely illustrativeand not at all limitative. In such examples, the parts are by weight andthe temperatures are in degrees centigrade.

Example 1 47 parts of the aminoazo dyestutf, obtained by coupling onemole of diazotizedl-(4'-aminobenzoylamino)-2-hydroxy-3-carboxybenzene-5-sulfonic acid withone mole of 3-amino-l-methylbenzene, are dissolved in 2000 parts ofwater with addition of sodium carbonate until there is a distinctalkaline reaction, and then, at 5 and while stirring, fumaric aciddichloride is added until no free amino group can be detected.

The thus-prepared dyestufi is precipitated with the aid of sodiumchloride (common salt) at 60-70, filtered off, and finally dried. Itsyellow dyeings on cotton, as such and also following aftercoppering, areof outstanding fastness to light. The dyestuif corresponds to theformula r-rQ Qr-r- H O I H SOsH 2 If, instead of the 47 parts of theaminoazo dyestuff from diazotized 1-(4-aminobenzoylamino)-2-hydroxy-3-carboxybenzene-S-sulfonic acid and S-amino-l-methylbenzene, 47 parts ofthe aminoazo dyestufiE from one mole of1-(4'-amiuobenzoylamino)-3-carboxy-4-hydroxybenzene-S-sulfonic acid andone mole of 3-amino-1-methylbenzene are reacted with fumaric aciddichloride according to the foregoing prescriptions, there is likewiseobtained a yellow cotton dyestutt of excellent properties.

6 Example 2 51.3 parts of the aminoazo dyestuif, obtained by couplingone mole of diazotized 1-(4'arninobenzoylamino)-2-hydroxy-3-carboxybenzene-S-sulfonic acid with 1 mole of3-amino-l-acetylarninobenzene, are dissolved in 1200 parts of water withaddition of sodium bicarbonate until there is a distinct alkalinereaction, and then, at 0-5 and while stirring, fumaric acid dichlorideis added until no free amino group can be detected.

The formed dyestufi is precipitated with the aid of common salt at about70, filtered OE, and finally dried. It dissolves in water with yellowcoloration and dyes cotton in pretty yellow shades which, as such aswell as when after coppered, are of very good fastness to light. The newdyestufi corresponds to the formula A similar dyestuif is obtained when,in the foregoing, the fumaric acid dichloride is replaced by mesaconicacid dichloride.

If, instead of the aminoazo dyestuff from diazotized 1 (4aminobenzoylamino) 2 hydroxy 3 carboxybenzene 5 sulfonic acid and3-amino-l-acetylamiriobenzene, an equivalent quantity of the aminoazodyestuif prepared by coupling one mole of diazotizedl-(4-aminobenzoylamino) 3 carboxy 4 hydroxybenzene 5 sulfonic acid withone mole of 3-amino 1 acetylaminobenzene is reacted with fumaric aciddichloride according to the foregoing prescriptions, there is likewiseobtained an excellent cotton dyestutf of the formula HO OC ei G r Has H9 It], A 0

to 41H: 2

Example 3 46.5 parts of the aminoazo dyestulf, obtained by coupling onemole of diazotized l-(4'-aminobenzoylamino)- Z-hydroxy 3carboxybenzene-S-sulfonic acid with one mole of phenylaminomethanesulfonic acid and splitting off the CH2SO3H group, are dissolved in 1000parts of water with addition of sodium bicarbonate until the reaction isdistinctly alkaline and then, at 0-5 and while stirring, fumaric aciddichloride is added until no free amino group can be detected.

The resultant disazo dyestuif is precipitated at about 70 with the aidof sodium chloride, filtered off, and finally dried. Its dyeings oncotton are pure yellow and, as such or in the form of the aftercoppereddyeings, have very good fastness properties. The dyestufi corresponds tothe formula A OaH 2 Example 4 543 parts of the aminoazo dyestufi,obtained by coupling one mole of diazotized l-(4'-aminobenzoylamino)- 2hydroxy 3 carboxybenzene 5 sulfonic acid with one mole of3-amino-l-carbethoxyaminobenzene, are dissolved in 900 parts of waterwith addition of sodium carbonate until the reaction is distinctlyalkaline and then, at -5 and while stirring, fumaric acid dichloride isadded until no more free amino group can be detected.

The formed disazo dyestufi, isolated in accordance with the procedureset forth in the preceding examples, yields yellow dyeings on vegetablefibers, which dyeings-- as such or in the aftercoppered state-arecharacterized by excellent fastness properties.

The same dyestufi is obtained when use is made, in the preceding, offumaric acid dibromide instead of fumaric acid dichloride.

It corresponds to the formula H00..- l wgmgi rml H g H ii (300 C2115SOaH 2 Example 35.1 parts of the aminoazo dyestulf, obtained by couplingone mole of diazotized l-amino-3-carboxy-4-hydroxybenzene-S-sulfonicacid with one mole of 3-aminol-methylbenzene, are dissolved in 800 partsof water with addition of sodium carbonate until the reaction is dis-If, instead of the aminoazo dyestufi from the fumaric acid dichloride isreplaced by mesaconic acid dichloride. V If, instead of the aminoazodyestulf prepared from 1 amino 3 carboxy 4 hydroxybenzene 5 sulfonicacid and 3-amino-l-rnethylbenzene, an equivalent quantity of theaminoazo dyestulf prepared from 1 mole of diazotized 1 amino 3 carboxy4- hydroxybenzene S-sulfonic acid and onemole'of l -amino-2methoxy-5-.methylbenzene is reacted with fumaric aciddichloride; there is likewiseobtained a valuable dyestutf which dyes cotton reddish-yellow. Thisdyestutf corresponds to the formula Example 6 48.5 parts of the aminoazodyestuff, obtained by coupling'one mole of diazotized2-hydroxy-3-carboxy-4'- amino-l,1-diphenylurea-S-sulfonic acid with onemole of 3-amino-l methylbenzene are dissolved,together with the quantityof sodium bicarbonate necessary for a weakly alkaline reaction, in 800parts of water and then, at 0-5 and while stirring, fumaric aciddichloride is added until no more free amino group can be detected, i.e. until no more diazotizable dyestufl is present. The weakly alkalinereaction can be maintained during the addition of the fumaric aciddichloride and until the reaction is terminated, by the intermittentaddition of small portions of additional sodium bicarbonate.

The dyestufl, isolated as described in the preceding examples, is abrown powder which dissolves in water with yellow coloration. Itpossesses a strong afli'nity for vegetable fiber. Its cotton dyeings, assuch or in the aftercoppered state, have excellent fastness properties.

The identical dyestuif is obtained when, in the foregoing, the fumaricacid dichloride is replaced by fumaric acid dibromide.

It possesses the formula The2-hydroxy-3-carboxy-4-amino-l,l'-diphenylurea-5- sulfonic acid, as astarting material, is prepared by condensing an alkali metal salt of thel-arnino-2-hydroxy-3- carboxybenzene-S-sulionic acid with4-nitrophenylisocyamate in an aqueous solution and subsequently reducingthe nitro group in usual manner, e. g. by treating the condensationproduct with sodium disulfide.

The following table sets forth examplesof additional dyestuffs whichcanrbe produced according to the present invention by following theprescriptions of the preceding art-13,856

iframples, using equivalent amounts of the corresponding dichloride isuniformly added within one hour until free reactants: NH: is no longerdetectable. The reaction solution is Elg p Dyestufi Formula. Dyeing onCotton I OH 7 v t 7. HOOC NHE-N=N NHENH== yellow.

I NH-OOOCHLCHpCHtJ S Cali 2 0H 0 0H; o. HO 0 c Nnc-N=N-mzo cn== reddishH 3 yellow. 0 l a SOaH J2 no 0({3 00m OCH: 1 HOQNE MQW M 035 HaC- -CH321H: 2

H 00. 1106a em I i 0 J HOaS NHCOCH:

H000 0011s 14.. H0 N=N N'EfiCHL orange. I 4 o H'OsS NHCOCHJ -L Examplemaintained weakly alkaline (pH of about 8.0) throughout 129 parts (0x05mole) of ltazow this operation by the dropwise addition of diluteaqueous benzeue-S-carhoxylic acid are dissolved with 25 parts sodiumhydroxide 501mm The dyesmfisoluuon t ((105 1 of 4-h d -5- m warmed to80, after which the obtained dysetulf mixture amino) benzoylamino 5'rnethoxy 1,1 b is salted out and filtered off. It is a yellow-brownpowder, 3-sulfonic, acid in 2500 par-ts of wat r i h h aid f theasymmetrical constituent of which corresponds to the sodium hydroxideuntil there is a weak alkaline reaction formula OCHs SOSH, no-lOrhNONn-co on=on o worn-Q 0 0--NH -N=NC OH HOOCI'J Ha COOH (P of about 8.0). Thesolution is cooled to 5 by theand which dissolves with yellow colorationin water, and addition of ice; thereupon, at the said temperature andvdyes cotton and fibers of regenerated cellulose 1n clear while stirringthoroughly, a 20% solution of fumaric acid yellow shades. The dyeings,especially when they are 11 treatedwith copper-yieldingagents, possessgood .f a t to Hghtand to W t'treatmen'ts.

"Similar dyestuffs of the same excellent properties are obtained when,on the one hand, the 4-hydroxy-4'-amino- 1,l'-azobenzene-3-carboxylicacid of the present example is replaced by an equivalent quantity of4-hYClIOXY-5r methyl 4' amino 1,1 azobenzene 3;- carboxylic acid, 4hydroxy 6 methyl 4 amino 1,1 azobenpound, obtained by the acid couplingof diazotized 1-(4' amino 3' methyl) benzoylamino 3 carboxy 4-hydroxybenzene sulfonic acid with l amino 3 methylbenzene, and 16.9parts (0.05 mole) of 4-hydroxy5-carboxy-4'-amino-l,1'-azobenzene-3-sulfonic acid are dissolved in 2200parts of water with the aid of an excess of lithium carbonate, and then,following the procedure I set forth in Example 16, a mixture of 90 partsof fumaric zene-3-carboxylic acid, 4-hydroxy-2'-chloro-4'-amino-l,1'-,,

azobenzene-S-carboxylic acid, or4-hydroxy-4'-a'minol,l'-azobenzene-3,3'-dicarboxylic acid, and/ or onthe other hand the 4-hydroxy-S-carboxy-2'-methyl-4'-(4"-amino)-benzoylamino 5' methoxy 1,1 azobenzene 3 sulfonic acid is replaced by anequivalent quantity of 4- HOQNH-CO-QN:

Example 16 37.5 parts (0.075 mole) of 4'-hydroxy-5-carboxy-2'- methyl 4'(4" amino) benzoylamino 5' methoxyl,1-azobenzene-3-sulfonic acid and62.5 parts (0.125 mole) of 4-hydroxy-5-carboxy-2'-methyl-4'-(3"-amino)-benzoylamino-S'-methoxy-1,1-azobenzene-3-sulfonic acid are dissolved in3000 parts of water at a pH of about 7.0 with the aid of dilute aqueoussodium hydroxide solution, and the resultant solution is cooled to about5 with crushed ice. After the addition of 40 parts ofN,N-dimethylaminobenzene, a 20% solution of symmetrical maleic aciddichloride (B. P. mm.: 79; (14 1.432) in 1,2-dichlorobenzene is addeddropwise, uniformly and slowly and while stirring thoroughly, until freeNHz is no longer detectable. The dyestufi solution is then adjusted toalkalinity to Brilliant Yellow with the aid of sodium carbonate, thetemperature raised to 80 to 90, the dyestulf salted out of the solutionwith the aid of sodium chloride, and the precipitate collected on afilter. Dried and ground, the product is a brown powder, theasymmetrical constituent of which corresponds to the formula HOaS andwhich dissolves with yellow coloration in water. Its clear yellowdyeings on cotton or fibers of regenerated cellulose are characterizedby goodfastness torlight and to wet treatments, particularly when theyare treated with copper-yielding agents.

Very similar dyestufis, which also have very good fastness properties,are obtained when, instead of symmetrical maleic acid dichloride, use ismade of an equivalent amount of the dichloride or dibromide ofmethylfumaric acid or of chlorofumaric acid or of bromofumaric acid, orof a mixture of two or more of these dicarboxylic acid dichlorides ordibromides.

Example 17 acid dichloride, 10 parts of symmetrical maleic acid di-.chloride and 400 parts of methylbenzene is added until no free NHz isdetectable. The resultant condensation product--isolated, dried andgroundis a yellow-brown powder, the asymmetrical constituent of whichcorresponds to the formula OOH . and which dissolves with yellowcoloration in water and dyes cotton and fibers of regenerated cellulosein clear yellow shades which, particularly after treatment with;

copper-yielding agents, are characterized by good to very good fastnessto light and to wet treatments.

Similar disazo dyestutf mixtures, having similar excellent properties,are obtained when, on the one hand, the diazo component of the firstaminomonoazo compound of this example is replaced by l-(3'- or4'-amino)- benzoyl amino 3 carboxy 4 hydroxybenzene 5 sulfonic acid orl-(4'-amino)-benzoylamino-2-hydroxy-3-' carboxybenzene-S-sulfonic acidand/ or on the other hand the azo component is replaced byl-arnino-3-acetylaminobenzene or l-amino-2-methoxy-5-methylbenzene. The

first aminomonoazo compound can also be replaced by an aminomonoazocompound obtained by coupling diazotized l amino 3 carboxy 4hydroxybenzene 5- sulfonic acid with 1-amino-3-methylbenzene or l-amino-Z-methoxy-S-methylbenzene or l-amino-3-acetylaminobenzene, followed byreaction of the resultant aminomonoazo compound with4-nitrobenzene-l-carboxylic acid chloride or3-nitro-4-methoxybenzene-l-carboxylic acid chloride and reduction of thenitro group to the amino group.

Similar dyestufis are also obtained when, in the foregoing, the4-hydroxy-5-carboxy-4'-amino-l,1-azobenzene- 3-sulfonic acid is replacedby an equivalent amount of 4 hydroxy 5 carboxy 2' -'butyrylamino 4'aminol,l-azobenzene-3 sulfonic acid or of 4-hydroxy-5-car;

boxy 2' methyl 4' amino 5 propoxy 1,1 azobenzene-3-sulfonic acid or of3-acetylamino-4-hydroxy- SOtH z 0 CH: HOQNEN NH-C OONE-C O-CH=GH-Q O-NH0 C m H. QM i H; I 00H 5-carboxy-4'1arnino-1,l'-azobenzene-2'-sulfonicacid or of 3 -formylan1ino 4 hydroxy 5 carboxy 4' aminol,l-azobenzene-2'-sulfonic acid or of 3-nitro-4-hydroxy- 5 carboxy 4'amino l,l azobenzene 2' sulfonic acid or of S-carbomethoxyor-carboethoxy-amino-4-hydroxy 5 carboxy 4 amino 1,1 azobenzene 2'-"sulfonic acid.

Example 18 50-10 by the addition of ice and then, while stirring- 72.6parts (0.15 mole) of the aminomonoazo comthoroughly, a benzene solutionof tumaric acid dichloride 1s 1i is added, in the course of l to 2hours, until free amino Water With. the aid of dilute aqueous sodiumhydroxide can no longer be detected in the reaction solution. Thesolution and are condensed as described in E p e '1 formed disazodyestuff is precipitated from the reaction with fumaric acid dichloride.During the condensation solution at 80 by the addition of a smallquantity of the pH value is held at approximately 7-8 by adding sodiumchloride, after which the precipitate is filtered small amounts oflithium carbonate. The resulting dyeofl? and dried. The product thusobtained corresponds to stuff is precipitated, filtered, Washed anddried. It is a the formula brown powder which corresponds to the formula[no N=N--OH=CHONHCOCH: HOOCI} S OsH S OsH .J:

and possesses good afiinity for cotton and for fibers of i regeneratedcellulose; its dyeings, treated with copper- =N yielding agents, arebrown-orange and possess good J fastness properties. H000 C1 Example anddissolves with orangeyellow coloration in water and 304 parts of f iacid di [3'. lf .4' i 1 15 with red coloration in concentrated sulfuricvacid. Its

diphenyl-(4)]-amide are dissolved in 400 parts of water copperedreddish. Yellow dyeings i 9 fibers of: in the form of the disodium Salt69 parts of sodium regenerated cellulose are characterized by excellentfastnitrite are added to the resultant solution, and then sufmess Ilight f Wet treawcntsficient ice to bring the temperature of the massdown to A snmlar dlsazo dyestufi 1s obtamed mstead'of At thistemperature and in the course of 20 to 30 the 58.2 parts of theamlnornonoazo compound of the minutes, 80 parts of 15% hydrochloric acidare added a made P Y Y- dropwise. The resultant acid tetrazo suspensionis stirred 25 ammo-1,132017813611633 "dlcarboxyllc acidfor about 3 hoursat 5 and then, after decomposing Example 21 excess nitrous acid by meansof urea or aminosulfonic acid, it is slowly added to an ice-coldsolution, containing 23.5 parts (05,05 mole) of the ami-nomonoazocompound, an excess of sodium carbonate, of 25 parts of l-acetopreparedby the acid coupling ofvdiazotized l-(4'-amino.)-

acetylamino-4-hydrozybenzene-3-carboxylic acid and 500benzoylaminoi-hydroxy-3-carboxybenzene-5-sulfonic acid parts of water.Upon completion of the coupling, the with 1+amino-3-methylbenzene, and23.8 parts (0..05

mass is heated to 70-80", and the resultant -disazo .dyemole) of theaminodisazo compound prepared by the stuff isolated. Dried and ground,it is an olive-brown acid coupling of diazctized4"-amino-.l,1'-azobenzene-v powder, which corresponds to the formula4,3'-disulfonic acid with :1-amino-3-methylbenzene are and whichdissolves with yellow coloration in water. Its together dissolved inwater with the addition of aqueous dyeings on cotton and fibers ofregenerated cellulose are, sodium hydroxide solution, and then treatedat 5.-10 after treatment with copper-yielding agents, yellow and andwhile stirring with "fumaric acid dichloride until are characterized bygood fastness properties. free amino is no longer detectable. Duringthis pro- If, in the-preceding paragraph, the 30.4 parts of fumaric 4cedure, the reaction solution is kept constantly weakly aciddi-[3'-sulfo-4'-amino-l,1-diphenyl-(4)l-arnide are alkaline by runningin a 10% aqueous sodium carbonate replaced by 22.8 parts of fumaric aciddi-(3'-sulfo-4'- solution. The thus-produced dyestufi mixture isseparated aminophenyl)-arnide and/or the 24 parts of l-acetoout with theaid of sodium chloride at 7080, afteracetylamino-4-hydroxybenzene-3-carboxylic acid are rewhich it isfiltered oil and then dried under reduced placed by 24 parts of1-(3'-carboxy-4-hydroxy)-phenylpressure. It dissolves in water withgolden yellow colora- 3-methyl-5-pyrazolone, a disazo dyestufl havingsimilar tion and dyes cotton and fibers of regenerated cellulose goodproperties is likewise obtained, the copperedtdyeings in light-fastbeautiful yellow-orange shades. The fastness being somewhat more reddishyellow than those of the of the dyeings to Wet treatments is .enhancedby afterdisazo dyestuff obtained according to the preceding treatmentwith copper-yielding agents. Theasymmetrical paragraph. component of themixture corresponds to the formula HOaS NH4JOON=N NH-'oo-cn=cn-c ONHQ-N;NN= @som HOOC OH H: H: SOaH If, instead of 24 parts of1-acetoacetylamino-4-hydroxy- Dyestufis with similar properties areobtained when, benzene-3-carboxylic acid, 14 parts of l-hydroxybenzeneinthe first aforementioned aminomonoazo compound, the Z-carboxylic acid or17.5 parts of 1-hydroxy-6-chlorol (4' amino) benzoylamino 2 hydroxy 3carbenzene-Z-carboxylic acid or 22 parts of 1-hydroxy-6-boxybenzene-S-sulfonic acid isreplaced by 1-(4'-amino)-bromobenzene-Z-carboxylic acid are employed, and thebenzoylamino-3-carboxy-4-hydroxybenzene-S-sulfonic acid coupling carriedout in weak caustic alkaline medium, and/or the l-amino-3-methylbenzeneis replaced by anvaluable dyestuffs are also obtained, the yellowcoppered other amine of the benzene series which is capable of dyeingson cotton or fibers of regenerated cellulose coupling, such for exampleas 1-amino-2,5-dimethylpossess good fastness properties. benzene,l-amino-2-methoxy-5-methylbenzene, 1-amino-. 3-acetylaminobenzene, .1amino-3-benzoylarninobenzene,. Example 20 58.2 parts of4-hydroxy-2'-chloro-4'-amino-l,1-azoacetylaminobenzene, etc. Somewhatmore .reddish dyebenzene-3-carboxylic acid are dissolved in 3000 partsof stuiis with similar good properties are obtained when, in

l amino2,5-dirnethoxybenzene, l-amino-Z-methoxy v -5- .the firstparagraph of the present example, the aminodisazo compound of theinitial mixture is replaced by an aminodisazo compound obtained bycoupling a diazotized 2-aminonaphthalene-4,8- or -5,7- or -6,8-disulfonic acid with one of the attire-enumerated amines of thebenzene series, diazotizing the resultant aminomonoazo compound, andagain coupling with one of the said amines of the henzene series.

Example 22 37.3 parts (0.05 mole) of the aminodisazo compound, preparedby coupling 1 mole of tetrazotized l-amino-4-(4'-amino)-benzoylamino-benzene first with 1 mole oflhydroxybenzene-Z-carboxylic acid and then with 1 mole of 2 (4' amino)benzoylamino 5 hydroxynaphthalene- 7-su1tonic acid, and 12.9 parts (0.05mole) of 4-hydroxy- 4'-arnino-1,lf-azobenzene-3-carboxylic acid aretogether dissolved neutral in water with the addition of aqueous sodiumhydroxide solution. Into the resultant solution,

there are simultaneously added dropwise and with good stirring a mixtureof 7.7 parts (0.05 mole) of fumaric acid dichloride and 8 parts ofbenzene, as well as such quantity of an aqueous sodium carbonatesolution as is necessary to keep the reaction of the condensation massweakly alkaline throughout. After all the fumaric acid dichloride hasbeen added, the mixture is further stirred until free amino is no longerdetectable therein. Thereupon the produced dyestufl mixture isprecipitated from the warm mixture with the aid of sodium chloride, andthe precipitate then filtered OE and dried. It is a dark red powder,which dyes cotton and fibers of regenerated cellulose in yellowish redshades of good dischargeability and fastness to light, the fastness ofthe dyeings to wet treatments being improved by aftertreatment withcopperyielding agents. The asymmetrical component of theproductcorresponds to the formula Dyestuffs with similar properties areobtained when, on the one hand the 1-hydroxybenzene-2-carboxylic acidused in preparing the first-mentioned aminodisazo compound is replacedby.l-hydroxy-6-methylbenzene-2-carboxylic acid and/ or the2-(4'-amino)-benzoylamino-5-hydroxynaphthalene-7-sulfonic acid isreplaced by 2-(3'- amino) benzoylamino 5 hydroxy naphthalene 7 sulfonicacid or 2-(3-amino-4'-methyl)-benzoylarnino-5-hydroxynaphthalene-7sulfonic acid or2-(4-amino)-benzoylarnino-6-hydroxynaphthalene-8-sulfonic acid or 2-amino-5-hydroxynaphthalene-7-sulfonic acid and/ or, on the other hand,the 4-hydroxy-4'-,amino-1,1'-azobenzene-3- carboxylic acid is replacedby an equivalent quantity of 4 hydroxy 5 methyl 4' amino 1,1 azobenzeneB-carbexylic acid or 3-carboxy-4-hydroxy-4'-amin0-1,1azobenzene-S-sulfonic acid or 4'-(4"-amino)-benzoylamino 3 carboxy 4hydroxy 1,1 azobenzene 5 sulfonie acid or one of the aminoazo compoundsobtained by coupling diazotized1-(4-amino)-henzoylamino-3-carboxy-4-hydroxybenzene-S-sulfonic acid withl-amino-2- methoxy-S-methylbehzene or by coupling diazotized l,-(4'-amino) benzoylamino 2 hydroxy 3 carboxybenzene-S-sulforiic acid withl-amino-S-methylbenzene.

Example 23 By replacing the 0.05 mole of the first aminomonoazo compoundin Example 15 by 0.05 mole of 4-hydroxy-5- carboxy 2' methyl 4' (3"chloro 4" amino) benzoylamino-5-methoxy-1,l'-azobenzene-3-sulfonic acidor of4-hydroxy-5-carboxy-2-methyl-4'-(3"-amino)-benzoylamino-5'-methoxy-1,l'-azobenzene-3-sulfonicacid or of 4-hydroxy-5-carboxy-4'-(3"-methylor -ethy1-4"-amino)-benzoylamino-l,l'-azo-benzene-3-sulfonic acid or of4-hydroxy-5-carboxy-4'-(3"-amino-4"-methoxyor eth0xy-benzoy1amino-1,1'-azobenzene-3-sulfonic acid or of4-hydroxy-5-carboxy-2-acetylamino 4' (4"-amino)-benzoylamino-l,l-azobenzene-3-sulfonic acid or of 4-hydroxy 5carboxy-2'-(2"-carboxy)-benzoylamino-4-(4- amino) benzoylamino 1,1azobenzene 3 sulfonic acid, and/ or by replacing the 0.05 mole of4-hydroxy-5- carboxy 2' methyl 4' (4" amino) benzoylamino5'-methoxy-1,1-azobenzene-3-sulfonic acid by 0.05 mole of a monoazocompound obtained by the acid coupling of diazotized 1-(3' or4'-amino)-benzoylamino-2-hydroxy-3- carboxybenzene-S-sulfonic acid or1-(3- or -4'-amino)- benzoylamino 3 carboxy -4 hydroxybenzene 5 sulfonicacid or l-(3-amino-4'-chloro or-bromo)-benzoylamino-3-carboxy-4-hydroxyhenzene-5-sulfonic acid withl-amino-3-methylbenzene or l-amino-Z-methoxy-S-methylbenzene orl-amino-3-acetylaminobenzene, and otherwise proceeding after the mannerdescribed in Example 15, there are likewise obtained dyestufi mixtures,the coppered dyeings of which have good fastness to light and to wettreatments.

- The following table sets forth further valuable dyestufis which may beprepared according to one of the procedures set forth in Examples 1-18,21 and 22. For example, one mole of aminoazo compound AA and one mole ofHOOC- aminoazo compound AB can be bound together with one mole offumaric acid dihalide. However, the aminoazo compounds AA and AB canalso be used in other proportions, as for example in the proportions of0.3 or 0.5 or 0.7 or 0.9 or 1.2 or 1.4 or 1.6 or 1.8 moles to 1.7 or 1.5or 1.3 or 1.1 or 0.8 or 0.6 or 0.4 or 0.2 mole, respectively, with theprovision that in any event two moles of aminoazo compound are reactedwith one mole of fumaric acid dihalide.

Instead of a fumaric acid dihalide, use may be made of symmetricalmaleic acid dichloride, a chlorofumaric acid dihalide, a bromofumaricacid dihalide or a methylfumaric acid dihalide. The properties of thethus-obtained dyestufis are similar to those obtained with fumaric aciddihalide, the shades vary only very slightly from those of the fumaricacid products.

Also suitable as acid-binding agent, for binding the hydrogen halideevolved during the condensation, are for example the hydroxide orcarbonate or acetate of lithium, sodium or potassium, calcium oxide orcalcium carbon- 7 ate, magnesium oxide, N,N-dimethylaminobenzene, etc.

2 Shade on Cotton (1) Condensation of Fumaric Acid Dihalide with-Example Aminoazo Compound AA Aminoazo Compound AB Direct C'opperedDyeing yeing 24 1 amino 4 (4 nitro) benzoyl amino ben 1 amino 3 carboxy4 hydroxy benzene 5 red-orange red-orange; zene 2 sulfonic acid 1hydroxy sulionic acid r 1 amino 3 acetyl benzene 2 carboxylic acid andreduction ammobenzene.

--+ 1-amino-3-methy1benzene.

2 1 amino 3 carboxy 4 hydroxy benzene 5 same as AA yellow yellow.

sulfonic acid 1 (4 amino) phenyl 3methy1-5-pyrazolone.

26 1 amino 3 carboxy 4 hydroxy benzene 5 Same 88 AA i d; D0.

sulfonic acid 1 amino 4 acetoacet ylamino-benzene.

27 do 1 ammo 3 carboxy 4 hydroxy benzene .-do Do.

sulfonic acid 1 (3 amino) phenyl 3-methy1-5-pyrazolone.

28 l amino 3 carboxy 4 hydroxy benzene 5 Same as AA Ye ow-Orange. S'OW-Omnge,

sulfonic acid 1 (4 -amino) -phenyl- 3 methyl 5 pyrazolone 1 amino8-methylbenzene. i

29 do l amino 3 carboxy 4-hydroxy benzene 5 do..l. Do.

sulfonic acid 1 amino 4 aeetoacetylamino benzene I amino 3methyl-benzene.

s0 1-amino-3-carboxy-4-hydroxy-benzene-5- 0 -.-d0 Do;

sulfonic acid 1 amino 4 acetoace tylamino benzene 1 amino 3 methylbenzene.

31 1 amino 3 carboxy 4 hydroxy benzene 5 same as AA brown 4 brown.

sulfonic acid 1 aminonaphthalene 6 sulfonic acid 1 amino 3 methylbenzene. p

22 3 carboxy 4 hydroxy- 4 amino 1,1 azo same as AA v yellow.benzene-5-sulfonic acid. t, v

33 3 carboxy 4 hydroxy 4 amino 1, 1' -azo Same as AA Do.

benzene 5 sultonic acid 1 (4 amino)-phenyl-3-methyl-5-pyrazolone.

34 do 3 carboxy 4 hydroxy 4 amino 1, 1 ezo Do,

benzene-5-sul1'onic acid.

35 1 amino 2 hydroxy 5 nitro benzene 3 same as AA Do.

carboxylic acid 1 (4' amino) phenyl 3 methyl 5 pyrazolone 1amino-3-benz0y1aminobenzene.

36 4 hydroxy 4 amino 1, 1' azo benzene 2-aminonaphthalene-6, 8-d1sulionic acid do D 3-carboxylic acid. 1-am no-3-ethylbenzene.

37 do 3 ammopyrene disulionlc acid 1 reddish yellow reddish yellowamino-2,5-dimethylbenzene. e V

38 do 1 aminobenzene 4 sulfonic acid 1 yellow yellow,

amin0-2-methoxy-fi-methyhbenzene, f

39 do 1-amino-3 carboxy-4-hydroxy-benzene-6- do D sulionic acid 1 amino3 propionyl aminobenzene.

40 1- (4-amino) -benzoylamino-2-hydroxy-3- 0 i. do Do;

carboxybenzene 5 sulfonic acid 1 amino-El-methylbenzene.

41 do 2 aminonaphthalene 4, 8 disulfonic acid do Dl-amino-2-methoxy-E-methylbenzene.

42 1 amino -3 carboxy 4 hydroxy benzene 5 3 carboxy 4 hydro ry 4 aminol, l azo reddish yellow. orange.

sulfonic acid 1 amino 3 acetyl benzene-2 -su1fon1c acid 1-arnin'o--aminobenzene. 3 methyl benzene.

43 o 1 (4 ammo) benzoylamin'o 2 hydroxy -'3 yellow; reddish yellow.

carboxybenzene 5 sulionic acid -v 1- I amino 3 methylbenzene 1 amino 3methylbenzene.

44 do 3-carboxy-4-hydro2ry-2 -methyl-4 (4 do Do,

amino) benzoylamino 6 methoxy 1, 1 azobenzene 5 sulfonlc acid 1 amino 3methylbenzene. I

45 do 3 aminopyrene dlsulionie acid 1 orange orange,

amino-2-methoxy-S-methyl-benzene.

Example 46 tron of the coupling, the resultant solution is heated toparts of symmetrical fumaric acid di-E5-hydroxy-7-sulfonaphthyl-(Zll-amide are dissolved as the disodium salt in 800 partsof warm water. parts of crystalline Hood (in HOaS sodium acetate areadded to. the. solution, which is then cooled to 0-5 Thereupon, whilestirring thoroughly, an ice-cold diazo suspension, prepared by theindirect diazotization of 72 parts of l-(4'-amino),-benzoylamino-2-hydroxy-3-carboxybenzene-S-sulfonic acid, is runin. The suspension,having, a. weakly acid reaction, is then neutralized by the addition ofaqueous sodium bicarbonate solution in the course of 4 to 5 hours until.an alkaline reaction to brilliant yellow is obtained. Upon compleaboutand the produced disazo dyestutf salted out therefrom, filtered off, anddried: It corresponds to the formula and is a dark powder whichdissolves with red coloration in Water, and dyes cotton and fibers ofregenerated cellulose in red-shades. The=dyeings have-goodfastness'properties; the latter can be somewhat improved by treatmentwith copper-yieldingvagcnts.

To prepare the symmetrical fumaric'acid'di- [S-hydroxy-7-sulfonaphthyl-(2)il-amide, 239 parts" of.Z-amino-S-hydroxynaphthalene-l-sulfonicacid and 40- parts of crystallinesodium acetate are dissolved in- 2000' parts of 19 20 Water. Then, inthe course of 3 to 4 hours and while linkage, and is 1 when x denotesone of the groups having stirring thoroughly, a 40% solution of fumaricacid dithe formulae chloride in benzene isadded dropwise until no morefree amino is detectable. The condensation mass is then NH-C-C warmed to70-80, and the reaction product isolated and 5 dried.

and 7 Example 47 Dyeing with a representative dyestufi according to theiii i q present invention-for example any one of the dyestufis 10 0 ofthe preceding examples-may be carried out as follows: and each m is oneof the integers 1 and 2.

100 parts of cotton are entered at 30 into a bath 2. An azo dye whichcorresponds to the formula B000 1! y OOH wherein each of R1, R11, R2 andR22 stands for a radical selected from the group consisting of benzene,diphenyl, stilbene, naphthalene, 5-pyrazolone and acetoacetylaminophenylradicals, one y and one y each stands for OH, the other y and the othery being hydrogen, each w stands for a member selected from the groupconsisting of hydrogen, chlorine, bromine, lower alkyl, nitro,acylarnino For aftercoppermg, the dyed material is immersed for half anhour in a bath containing 2 parts of copper sulfate Ef 4031-1 v ai for afi i a and 2 parts of glacial acetic acid in 3000 parts of water at 8group conslstmg y rogen c orme mqlme an 0 then withdrawn, thoroughlyrinsed with water, methyl, the other v being hydrogen, and each n 1s oneof squeezed and driei the integers 1 and 2.

3. An azo dye which corresponds to the formula containing one part ofthe dyestufi and one part of Glaubers salt in 300'parts of water. Thetemperature is raised to the boil within half an hour, then 20 parts ofGlaubers salt are added and the bath is allowed to cool to The dyedmaterial is withdrawn and thoroughly rinsed 25 with water.

(N=N-R:).-1N=N-R1NHC OG|=(|JO 0NHRul-N=NR1(N=NRs) ..-1]..-1-N==NRq 0 U IH00 11 Having thus disclosed the invention, what is claimed is: whereineach of R1 and R2 stands for a member selected 1. Anazo dyestutt'corresponding to the formula from the group consisting of benzene,diphenyl, stilbene, j naphthalene, S-pyrazolone andacetoacetylaminophenyl radicals, each of R6, R1 and Rs stands for amember se- "E lected from the group consisting of phenyl and naphthylH00 v radicals, R9 stands for a member selected from the group I 1 45consisting of phenyl, naphthyl and pyrene-sulfonic acid i radicals, oney stands for OH, the other y being hydro- RPN=N [(RB N=N gen, w standsfor a member selected from the group con- Whel'ein each of R1, R6 and R7i for a member sisting of hydrogen, chlorine, bromine, lower alkyl,nitro, Selected from the group consisting of benzene, p yl acylamino and--SOaH, one v stands for a member se- Stilbene, naphthalene, -Py andacetoacetyl- 5O lected from the group consisting of hydrogen, chlorine,aminopheflyl radicals, R8 -K a member Selected bromine and methyl, theother v being hydrogen, and each from the group consisting of benzene 1and naphthalene n i ne f the integers 1 and 2. radicals, and Rs standsfor a member selected from the 4, An azo dyestufi according to claim 1wherein each v group consisting of benzene, naphthalene andpyrene-sulstands for hydrogen.

fonic acid radicals; x stands for a member selected from 5. A azodyestufi according .to claim 2 wherein each the group consisting of asimple linkage and one of the v stands for hydrogen.

groups having the formulae 6. An azo dyestufi according to claim 3wherein each v stands for hydrogen. -5Q- 7. The polyazo dyestuflcorresponding to the formula and H000 OO =N N-O-OH:

' QM l8 2,

i i i J2 8. The polyazo dyestufi corresponding to the formula r on one ystands for OH and the other y stands for hydrogen; w stands for a memberselected from the group con- HOOC- N-CO -c cn== sisting of hydrogen,chlorine, bromine, lower alkyl, nitro, v A k 8 acylamino and SOaH; one vstands for hydrogen and NH the other v stands for a member selected fromthe group consisting of hydrogen, chlorine, bromine and methyl; 0,11 s nis one of the integers l and 2 when x denotes a simple 21 9. The polyazodyestuif corresponding to the formula an w Hots

. H v 2 10. The polyazo dyestutf corresponding to the formula OaH 2 11.The polyazo dyestutf corresponding to the formula two moles of a mixtureof two different aminoazo compounds but which correspond to the sametype formula and two moles of a mixture of an aminoazo compound whichcorresponds to the formula and an aminoazo compound which corresponds tothe formula HzN-Ra[-N=NR7(-N=N'Rs),.-1]n-iN=NR9 wherein each of R1 andR2 stands for a radical selected from the group consisting of benzene,diphenyl, stilbene, naphthalene, 5-pyrazolone and acetoacetylaminophenylradicals, each of Re, R: and Rs stands for a member selected from thegroup consisting of phenyl and naphthyl radicals, R9 stands for a memberselected from the group consisting of phenyl, naphthyl andpyrene-sulfonic acid radicals, one y stands for -OH, the other y beinghydrogen, w stands for a member selected from the group consisting ofhydrogen, chlorine, bromine, lower alkyl, nitro, acylamino and -SO H,and each n is one of the integers 1 and 2, with one mole of adicarboxylic acid halide which corresponds to the formula wherein Astands for a member selected from the group consisting of hydrogen,chlorine, bromine and methyl, and 2 stands for a member selected fromthe group consisting of chlorine and bromine.

13. Process according to claim 12 wherein the dim!- boxylic acid halideis a fumaric acid halide.

14. A process for the manufacture of an azo dyestutf, which comprisesthe step of treating, in an aqueous medium and in the presence of anacid-binding agent, the aminoazo dyestulf of the formula H000 1}ICON=NH,

tH with the dichloride of the formula [Cl-G-CH-l:

15. A process for the manufacture of an azo dyestuff, which comprisesthe step of treating, in an aqueous medium and in the presence of anacid-binding agent, the aminoazo dyestuff of the formula SOIH 42H,

with the dichloride of the formula 16. A process for the manufacture ofan azo dyestutf which comprises the step of treating, in an aqueousmedium and in the presence of an acid-binding agent, the aminoazodyestufi of the formula with the dichloride of the formula [Cl-O-CHL 17.A process for the manufacture of an azo dyestutf, which comprises thestep of treating, in an aqueous medium and in the presence of anacid-binding agent, the aminoazo dyestuif of the formula 18. A processfor the manufacture of an azo dyestutf, which comprises the step oftreating, in an aqueous me diumand in the, presence of an acid-bindingagent, the

aminoazo dyestufi of the formula 11 N=N NH: 5 2,646,338

HOIS 229,425

with the dichloride of the formula 504,489

[Cl-(F-GHL 10 ,References'citedinthe file of this patent UNITED STATESPATENTS Scln'rm Ian. 4, 1938 Kappeler July 21, 1 953 FOREIGN PATENTSSwitzerland Ian. 17, 1944 Belgium July 31, 1951

1. AN AZO DYESTUFF CORRESPONDING TO THE FORMULA